I just installed Richard Sheperd’s TwentyTenFive HTML5 version of the default WordPress theme and Sylvia Egger’s Accessible Five accessibility enhancing child theme.
There was a slight glitch with the name of the TwentyTenFive folder name having changed, but all seems well now after I renamed it back to ‘TwentyTenFive’.
We can just hope these both quickly make into WP core. Especially as there was a recent call for WP accessibility contributions.